HELL hath no fury like a Little Mermaid spurned. In her Oprah interview, Meghan, Duchess of Sussex, compared herself to the benighted creature in the Walt Disney film. Defenders of the monarchy might see a closer fit with the shape-shifting Sea Witch who tries to take over Atlantica. Her devastating interview, in which she accused the royal family of racism, is potentially ruinous to this archaic and anachronistic institution, already struggling to make itself relevant in the 21st Century.

The Queen is still the Head of State in our constitution, as well as head of the Church of England. Her image is everything, a potent symbol of UK sovereignty abroad. Even the Scottish National Party buys into royal mystique and accords the monarch pride of place in its independence project. Not perhaps for much longer.

This crisis is arguably worse than the Abdication in 1936. Then, the monarchy was a robust and unchallengeable part of the British institutional landscape. Edward and his American divorcee went into convenient exile and relative obscurity. Meghan isn't going quietly. She is a destroyer – a heat-seeking missile, and she was bang on target.

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She accused the royal family of propagating falsehoods, failing in its duty of care, discriminating against her children, ignoring her suicidal tendencies and putting her family's life in danger by withdrawing protection. Her tale of victimhood has reverberated across the world and particularly in the Commonwealth of former British colonies. Nothing could be more damaging than the head of the Commonwealth being tainted with racism.

Meghan has at her back an army of international celebrities led by Hillary Clinton, who accused the royals of “outrageous cruelty” as if they'd held Meghan in a dungeon in the Tower. Brexit Britain was already being portrayed by the US media as a reactionary and xenophobic place. Now comes confirmation from within.

It hardly matters that much of what the Duchess said was nonsense. She claimed that during her pregnancy she was not allowed to visit her friends and was only allowed out twice in four months. If that's true the royals were guilty of coercive control, a criminal offence. The isolation, she said, contributed to her mental health problems and resulted in “suicidal thoughts” for which she was given “no support”.

She said that she approached the human relations office and was told they couldn't help because she wasn't an employee. This is hardly surprising. The Sussexes had their own private office staffed by well-paid people whose job it was to look after her welfare. They could have bought the best psychiatric help on the planet. Her husband, Harry, even co-founded a charity for people with mental health issues, Heads Together. Did he ignore his own wife's psychological deterioration?

A scene from the couple’s Oprah interview

A scene from the couple’s Oprah interview

Meghan complained that her son, Archie, had been blackballed by the Palace because of “concerns” about his colour. She says she was told he would not automatically be a prince, which is true since the Queen's great-grandchildren don't automatically take on the title. Archie could become a prince if and when Charles, his grandfather, becomes king.

But this was not about protocol, but race. She connected the unspecified “conversations” about his skin colour with the fact that Archie was being deprived of his royal title – at risk to his life. It's not clear which she thought was worse: the racism or the fact that she was told, again during her pregnancy, that her son would not have police protection.

Was she suggesting here that her protection officers would have been withdrawn because Archie was not immediately to become a prince? That is plainly wrong. The royal protection squad would never have been taken from Prince Harry and his family while he remained an active royal. Security costs only became an issue when the couple said they wanted to leave, “stand back”, from their royal roles and seek their fortunes in Canada and America. They couldn't have it both ways and continue to be funded by UK taxpayers after they'd departed for La La Land.

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In one of many startling revelations Harry said: “My family literally cut me off financially...”. His dad wouldn't answer his calls, either. That's obviously an issue for the Prince of Wales, who holds the purse strings. But the Sussexes weren't exactly left penniless. Harry had around £20 million from investments left by his mother and Meghan had her own millions. They are getting £100m from Netflix and Spotify. Harry said that “going to the streamers was never part of the plan”. Perhaps not, but since they intended to earn large sums of money to pay for their £11 million Santa Barbara mansion, media work must have been in the back of their minds.

There were predictable claims of racism in the British media. The press is disrespectful, sometimes cruelly so but, unlike social media, claims of actual racism against Meghan have never been substantiated. Yet the Duchess is now offering concrete proof that the royal family itself, the pinnacle of state privilege, is racist. Just how “dark” would Archie be?

This was the cruellest cut of all, and one the Palace cannot allow to stand. The context of the remark, or remarks, was not made clear. It was Prince Harry who heard it and he was refusing to “share” any more of the story. Yet he'd already shared the greatest possible libel of his own family. There can be no charge more damaging to a institution today than that it harbours racists.

Could it have been a misunderstanding? I was once accused of racism for saying that, when watching her legal drama Suits, it had never occurred to me that Meghan was black. It was only after she hooked up with Harry that I learned she was a Person of Colour. But if it was a similarly misconstrued remark, the Palace should make that clear. If it does not, the monarchy will be indelibly smeared.

It is said, jokingly, that Meghan's interview was a rehearsal for the next season of Neftlix's Crown. If the Palace doesn't clear this mess up it might be the last ever.

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